I tried searching for things like opposite of solid-state, but most of what I've found suggest things like liquid-state. I'm pretty sure a drive that is not solid-state contains no liquid to speak of.

Is there a one word antonym for the use of solid-state in this context?

  • 30
    – LarsTech
    Commented Nov 30, 2011 at 16:07
  • 2
    @LarsTech - or "Rust on the Run" ?
    – mgb
    Commented Nov 30, 2011 at 16:07
  • 3
    Colloquially I've also heard the term "spindles"
    – Andrew Vit
    Commented Nov 30, 2011 at 19:14
  • 4
    You mean one that actually has a disk in it?
    – GEdgar
    Commented Nov 30, 2011 at 19:18
  • 8
    Hence the acronyms SSD (solid state drive) and HDD (hard disk drive). Commented Dec 1, 2011 at 6:40

12 Answers 12


Solid-state drives are called solid-state because there are no moving parts in them. Drives with moving parts are called hard disk drives, because they contain disks which rotate when the drive is powered on. You could consider this an antonym, but not necessarily. They are simply two different technologies, with many other possible to come.

  • 12
    @kojiro: both are drives. One of them is SOLID STATE drive and the other is HARD DISK drive. You could call it a solid state disk, but NEVER solid state hard disk.
    – Frantisek
    Commented Nov 30, 2011 at 15:29
  • 2
    @kojiro en.wikipedia.org/wiki/Solid-state_drive and en.wikipedia.org/wiki/Hard_disk_drive
    – user11550
    Commented Nov 30, 2011 at 16:05
  • 25
    The term "solid state" means "made from transistors and/or integrated circuits". Just because a hard disk is a solid object, as opposed to liquid or gas, I suppose, doesn't make it "solid state". Phrases often have more specific meaning than their constituent parts. I could sit a desktop computer on my lap, but that doesn't make it a "laptop computer"! I could have a friend who is a girl, but that doesn't make her "my girlfriend". Etc.
    – Jay
    Commented Nov 30, 2011 at 16:38
  • 8
    @kojiro The reason why it was called a hard disk drive, was because the spinning platters inside (disks) were rigid. Later, disk mechanisms with removable soft platters were developed, these drives were called floppy disk drives and the media were called floppy disks. I suppose they used floppy instead of soft because the disk isn't soft like a marshmallow or pillow, but instead is flexible. I guess the engineers liked the whimsical sound of floppy rather than flexible disk drives
    – ghoppe
    Commented Nov 30, 2011 at 17:16
  • 7
    Young group. I'm surprised it took this long for someone to explain the "hard" drive part and not mention in the context "floppy".
    – surfasb
    Commented Nov 30, 2011 at 22:38

The word you are looking for is "magnetic" or "mechanical" (i.e. a mechanical disk drive).

The word "disk drive" has become very ubiquitous and a layman is likely to apply the term to other storage technologies. So, while technically you would be correct in saying that a disk drive is something that is not (technically) "solid-state", the term could easily be confused.

This is an English/communication question; not a technical one. The only way to guarantee understanding is to properly describe the specific technology you are referring to — mechanical disk drive, platter-based disk drive, old-style noisy rotating spinny magnetic planar disks with crashing heads inducing much rage systems — don't get too caught up in the technical accuracy when communication and understanding are important.

  • 3
    I see "magnetic" used almost as frequently as "mechanical", and in aggregate "spinning", "rotating", etc aren't far behind. All are equally over-broad. As Sean Vikoren pointed out evolution is messy; it might be a few years before this question can be revisited and given a definitive answer. Commented Nov 30, 2011 at 18:04
  • 1
    @DanNeely: I +1'd you, but actually I see "magnetic" more often.
    – Charles
    Commented Dec 1, 2011 at 2:33
  • Answer updated to include "magnetic." Commented Dec 1, 2011 at 2:39
  • I'd prefer "Electro-Mechanical Magnetic Storage" as the catch all, but this could also refer to tape. Commented Dec 1, 2011 at 14:23
  • This is the most correct answer. Although typically they are called "hard disk drive" to differentiate between solid-state and magnetic.
    – MikeMurko
    Commented Dec 1, 2011 at 17:38

I'd quibble with some of Rimmer's definitions, but his point is essentially correct.

I believe the real definition of solid state is something more like "made with transistors and/or integrated circuits". An old vacuum tube memory unit has no moving parts, either, but wouldn't be called solid state. Core memory had no moving parts, etc. (I don't mean to be critical; I'm sure someone could quibble with my definitions too. Just trying to clarify.)

Hard disk refers to a technology where data is stored on spinning, rigid disks. We call it hard to distinguish it from floppy disk, where the disks are flexible, and disk to distinguish it from drum storage, where data was stored on the outside of a cylindrical device, i.e. a device that was drum-shaped. (Drum drives have been obsolete for a long time and floppy disks are just about gone, I think.)

A CD is technically a disk that is hard, but we don't call it a hard disk because the technology is quite different and we need to distinguish.

Yes, by definition a hard disk drive is not solid state, just like by definition a cathode-ray tube is not a liquid crystal display, etc. I suppose you could make a disk-shaped solid state memory device, but we wouldn't call it a hard disk drive except as a joke.

Personally I think calling a solid state memory unit a drive is a misnomer, as I understand the word drive to refer to a device with a motor that spins something. But solid-state drives have picked up that name by analogy, I think; they're like a hard disk drive except that they're solid state.

And to ditto Rimmer, they're not really opposites; they are two of many existing and many more possible technologies. I've mentioned seven in this post: core memory, vacuum tubes, drums, hard disks, floppy disks, solid state, and CD. I'm sure in the future we'll see other technologies.

  • 1
    I find both these posts rather interesting, as I've always called them "solid-state hard disks", omitting the "drive" entirely - but also wrong because there is no disk in them!
    – Izkata
    Commented Nov 30, 2011 at 17:29
  • 1
    Prior to drum storage there was liquid storage. To temporarily store some bits of data there were liquid mercury tanks. The bits were encoded as waves that went down the tank and came back again. So there was liquid-state storage. But I agree with your definition of solid state from electronics. As technology progressed more devices (music players, controller systems, car computers, medical devices) progressed to solid state technology and became more reliable. An antonym of solid state in the electronics world (and not the hard disk world) might be analog.
    – jqa
    Commented Nov 30, 2011 at 17:56
  • That definition isn't entirely correct. Yes, Transistors are solid-state, but that doesn't mean everything else isn't. ie. a resistor network is solid-state. Example: en.wikipedia.org/wiki/Resistor_ladder
    – user606723
    Commented Nov 30, 2011 at 18:48
  • Agree that nothing is "driven" in a SSD so the name doesn't fit. FYI though, vacuum tubes contain a moving electron gas, and some tenuous internal gas as well (non-ideal vacuum or even on purpose to improve emission), so they are not solid state. Commented Dec 1, 2011 at 6:17
  • Wuser606723: Good point. See, I said some could quibble with my definition, too.
    – Jay
    Commented Dec 1, 2011 at 6:19

The typical acronyms and phrases are HDD for Hard Disk Drive and SSD for Solid State Drive.

The generic "parent" term is DD for Disk Drive.

Adding to this list is FDD for Floppy Disk Drive (remember those?), ODD for Optical Disk Drive (more common terms are CD, DVD & Blu-ray Drives though), Tape Drive and USB Flash Drive.

To answer your question though, there really is no opposite term, since hard disks aren't binary in their nature (yes pun intended)

  • I wonder if UFD has ever been used for USB Flash Drives...
    – Izkata
    Commented Nov 30, 2011 at 21:12
  • 2
    Technically, an USB Flash drive is a solid state drive. There is no difference except the package shape, connection method and capacity
    – edgerunner
    Commented Nov 30, 2011 at 21:33
  • 1
    The generic term is data storage device, perhaps omitting data or device. It should not include disk. Commented Dec 1, 2011 at 6:21
  • 1
    @Potatoswatter I agree with you, however Disk Drive (DD) is the common usage.
    – hafichuk
    Commented Dec 1, 2011 at 16:10
  • @Izkata: yes. It's not common, though.
    – Mathieu K.
    Commented Mar 7, 2017 at 5:55

Solid-state does not really have an opposite when it comes to this tech. Solid-state in this case refers to the quality of the hard drive; that it does not have moving parts and its internal memory storage is (simply) a solid, non-moving material. A standard hard drive has plates (disks) and arms that move and is, or at least was, called a "hard disk drive".

  • 7
    Fixed it's to its, which make my eyes bleed when used incorrectly.
    – Frantisek
    Commented Nov 30, 2011 at 15:13
  • Thanks for the fix, I often fat-finger that one when I'm typing quickly. Sorry that I made your eyes bleed.
    – Dave
    Commented Nov 30, 2011 at 17:40
  • 1
    Solid-state refers to the electronics that make up the storage mechanism. Commented Dec 1, 2011 at 4:54
  • It does have an antonym; mechanical.
    – Zelda
    Commented Dec 2, 2011 at 19:46
  • @RiMMER - It's the most bs english rule though.... I always write it that way and go back and correct it.
    – dwjohnston
    Commented May 21, 2014 at 11:17

The headline question, What do you call a disk drive that is not solid state?, actually reveals the answer, and also the confusion. The storage device that a solid-state drive (SSD) replaces is called a disk drive.

The confusion comes because, on the time scale of language evolution, the technology is new and the wording hasn't completely settled down. The original name for a disk drive was magnetic disk drive (which was equipment that rotated a magnetic disk), but because essentially all disks in the computer context were magnetic, the magnetic was dropped. When consumer PCs appeared, they first used only floppy disks (so called because the magnetic disks were flexible instead of the conventional rigid, or hard, disks). Then consumer PCs got higher-performing hard disk drives, which were usually called hard drives or hard disks to distinguish them from the earlier consumer disk drives which were used for floppies.

When the flash-memory-based replacements for hard disk drives appeared, they came to be called solid-state drives, which showed their function as similar to that of a disk drive, and their distinct nature, solid-state. There is no disk inside a solid-state drive, just integrated circuits (chips). The term solid-state dates way back to vacuum tube (British: valve) days, before transistors or chips. When invented, transistors (and similar things, like later chips) were called solid-state devices from the physics term solid which distinguished them from earlier devices using a vacuum. So solid-state was used for things built out of chips (like solid-state memory such as RAM), and so was used for the non-disk hard drive replacement, the solid-state drive.

Exactly what "opposite" means in the context is a little hazy, but it might be reasonable to say in the context of mass storage drives there are solid-state drives and disk drives (which could include optical disk drives as well as hard disk drives).

  • Also, solid state devices are not actually drives, since they contain no driven parts, unlike hard disk drives.
    – Kit Z. Fox
    Commented Nov 30, 2011 at 19:12
  • @kit: true, no mechanical thing is driven in an SSD, but electronics use the term driver for circuits that "push" the electrons into other circuits. They have drivers that drive the flash chips, in a very loose analogy to the motors that drive the disk in a hard drive. However, the term drive was presumably used to show the functional equivalence to existing drives rather than as a description of the internal nature.
    – mgkrebbs
    Commented Nov 30, 2011 at 19:29
  • +1 This is the most complete answer. The linguistic evolution and baggage is fascinating.
    – mskfisher
    Commented Dec 1, 2011 at 15:07

Spinning Disk

Most non-SSDs could accurately be called a "spinning disk drive".


I know this isn't a long answer like the others, but you might also consider Magnetic Storage. Magnetic Disk Drive would work as well.

  • Came here to say this. It's not an opposite as such but it's a reference to the technology, as is solid-state.
    – Matt
    Commented Nov 30, 2011 at 22:57
  • 1
    So there's solid state, magnetic, and optical. (CD and DVD variants and others are optical, not magnetic).
    – gnasher729
    Commented Aug 7, 2014 at 14:48

Hard Disk Drive (HDD) is typically used as the generic for non Solid State Drives (SSD).

Alternative "disk drives" include:

  • 5.25" Floppy Disk
  • 3.5" Floppy Disk (Floppy)
  • Compact Disk (CD)
  • Digital Versatile Disk (DVD)

Usually just be specific, rather than looking for an all-encompassing word, but usually it depends on context and why you're trying to differentiate.

Since the most common alternatives to solid-state drives are "hard disk drives" and "floppy disk drives", a common term to refer to non-SSD disks is "spinning media."

  • 1
    but it is also incorrect to call it a solid-state drive because nothing is driven :)
    – JamesRyan
    Commented Dec 1, 2011 at 12:39
  • @JamesRyan besides electricity.
    – kojiro
    Commented Dec 6, 2011 at 14:26
  • @JamesRyan Of course it is driven, the storage medium in the drive won't read/write itself, will it? In the traditional sense of the term "drive", the memory controller, all other circuitry, and the firmware in SSDs is the drive that allows data stored on the storage medium, which is typically a flash memory, to be accessed. See short terminology on computer storage
    – detic
    Commented Feb 28 at 7:37

The simple answer to your question is Non Solid State Drive

Why? Because Solid state drives are one family and there are others out there: Optical, Magnetic disk and tape drives to name a few. So it would be incorrect to say that Hard Disk drives are the opposite of Solid State drives.

Now if you are meaning to ask for the most common alternatives to Solid State drives, its probably Hard Disk Drives or optical media (cd/dvd/blue ray) which are alternatives to Solid State drives (depending on application)


I use the term mechanical or electro-mechanical drive.

Not the answer you're looking for? Browse other questions tagged or ask your own question.